In a field of business machines such as a copying machine and a facsimile machine, there has been known a machine with a built-in stapler which is driven by an electric motor or the like for the purpose of automatically binding sheets of paper which have been copied or received through these machines into stacks of every determined number of sheets. An ordinary stapler which is used on a desk has such a structure that a magazine adapted to successively ejecting staples which have been charged in the magazine against the sheets of paper to be bound, and a clincher adapted to fold tip ends of staple legs which have passed through the sheets of paper, are pivotally connected to each other at their one ends. However, the built-in stapler, which is built into the business machine as described above, is constructed in such a manner that a driver unit which is driven by an electric motor to successively eject the staples charged in the magazine against the sheets of paper to be bound, and a clincher unit for folding the tip ends of the staple legs which have passed through the sheets of paper to be bound along a back face of the sheets of paper, are provided independently from each other. Both the units are held on a frame of the machine independently from each other, so as to freely move with a determined distance therebetween. The sheets of paper to be bound are fed into a space between the two units, and by moving and driving the two units synchronously, stapling performance is conducted at desired positions of the sheets of paper to be bound. By constructing the stapler in this manner, a mechanism for pivotally holding the two units is not required between the driver unit and the clincher unit. Therefore, both directions for feeding and discharging the sheets of paper to be treated by the copying machine or the like can be freely designed. Accordingly, it is easy to design the machine, for example, in a manner of feeding and discharging the sheets of paper in a certain direction, and it is advantageous that treating speed can be improved.
However, in the above described built-in stapler, it has been necessary to recharge the staples into the magazine of the driver unit. Further, it may sometimes happen, although not so often, that the staple legs ejected from an ejecting passage formed at a forward end of the magazine of the driver unit cannot pass through the sheets of paper, but may be collapsed and jammed in the ejecting passage. In such cases, it has been necessary to move the driver unit to a home position to do a work for recharging the staples into the magazine of the driver unit, and a work for removing the jammed staples from the ejecting passage formed at the forward end of the magazine of the driver unit.
In the related mechanism, the driver unit and the clincher unit are held so as to move synchronously in a state where they are vertically aligned, and the home positions are provided at one ends of respective moving ranges of the two units in order to make the units aligned in position, to do the work for charging the staples and removing the jammed staples in a state where both the units have been moved to the home positions. However, since the home positions of the two units are set at the same position, the clincher unit will be positioned above the magazine of the driver unit in a state where both the units have been moved to the home positions. For this reason, there has been a problem that it has been difficult to do the work for charging the staples into the magazine of the driver unit or removing the jammed staples.